ELGIN, Ill. - An insurer has a duty to defend its insured and additional insured against an underlying antitrust lawsuit stemming from the insured's adoption of two ordinances requiring the use of radio transmitters, an Illinois appeals panel affirmed June 9 (American Alternative Insurance Co. v. Lisle Woodridge Fire Protection District, et al., No. 2-13-0803, Ill. App., 2nd Dist.; 2014 Ill. App. Unpub. LEXIS 1174).